Abstract: The main purpose of this study is to interpret the thermoplastic volumetric response of saturated clay during heating and cooling based on thermoplasticity. A two-yield-surface model for describing the thermo-mechanical behavior of both normally consolidated and overconsolidated saturated clay is proposed. Compared with similar existing models, the novelty of the proposed model lies mainly in two aspects: (a) a new equation directly expressing the thermoplastic strain with one additional parameter is proposed which is related to the stress condition and temperature increment; (b) a newly defined coupling mechanism of thermal and mechanical surfaces is used which is more concise. The capabilities of the proposed models to describe the observed experimental behavior were analyzed by predicting the thermal deformation of illite clay and loess suffering thermomechanical loading. Specifically, the accumulated volumetric strains in 1D conditions after multiple heating and cooling cycles were simulated and discussed.

一维应力状态下饱和黏土热应变响应本构研究

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